【摘要】 从定积分所具有的与对称有关的一个等式(命题1),得到关于定积分的另外一个等式(命题2)。联想到二重积分也会有类似的与对称有关的等式,于是得到命题3到命题10中的几个等式。更多还原

【Abstract】 An equality of definite integral (named proposition No. 2 in the essay) can be deduced from another equality of definite integral relating to symmetry(named proposition No. 1). Based on this fact, the author assumes similar equality of double integral relating to symmetry. Hence the equalities from proposition No. 3-No. 10 are deduced.更多还原